includes/password/PasswordPolicyChecks.php

   1 <?php
   2 /**
   3  * Password policy checks
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 use Cdb\Reader as CdbReader;
  24 use MediaWiki\MediaWikiServices;
  25 use Wikimedia\PasswordBlacklist;
  26
  27 /**
  28  * Functions to check passwords against a policy requirement.
  29  *
  30  * $policyVal is the value configured in $wgPasswordPolicy. If the return status is fatal,
  31  * the user won't be allowed to login. If the status is not good but not fatal, the user
  32  * will not be allowed to set the given password (on registration or password change),
  33  * but can still log in after bypassing a warning.
  34  *
  35  * @since 1.26
  36  * @see $wgPasswordPolicy
  37  */
  38 class PasswordPolicyChecks {
  39
  40         /**
  41          * Check password is longer than minimum, not fatal.
  42          * @param int $policyVal minimal length
  43          * @param User $user
  44          * @param string $password
  45          * @return Status error if $password is shorter than $policyVal
  46          */
  47         public static function checkMinimalPasswordLength( $policyVal, User $user, $password ) {
  48                 $status = Status::newGood();
  49                 if ( $policyVal > strlen( $password ) ) {
  50                         $status->error( 'passwordtooshort', $policyVal );
  51                 }
  52                 return $status;
  53         }
  54
  55         /**
  56          * Check password is longer than minimum, fatal.
  57          * @param int $policyVal minimal length
  58          * @param User $user
  59          * @param string $password
  60          * @return Status fatal if $password is shorter than $policyVal
  61          */
  62         public static function checkMinimumPasswordLengthToLogin( $policyVal, User $user, $password ) {
  63                 $status = Status::newGood();
  64                 if ( $policyVal > strlen( $password ) ) {
  65                         $status->fatal( 'passwordtooshort', $policyVal );
  66                 }
  67                 return $status;
  68         }
  69
  70         /**
  71          * Check password is shorter than maximum, fatal.
  72          * Intended for preventing DoS attacks when using a more expensive password hash like PBKDF2.
  73          * @param int $policyVal maximum length
  74          * @param User $user
  75          * @param string $password
  76          * @return Status fatal if $password is shorter than $policyVal
  77          */
  78         public static function checkMaximalPasswordLength( $policyVal, User $user, $password ) {
  79                 $status = Status::newGood();
  80                 if ( $policyVal < strlen( $password ) ) {
  81                         $status->fatal( 'passwordtoolong', $policyVal );
  82                 }
  83                 return $status;
  84         }
  85
  86         /**
  87          * Check if username and password are a (case-insensitive) match.
  88          * @param bool $policyVal true to force compliance.
  89          * @param User $user
  90          * @param string $password
  91          * @return Status error if username and password match, and policy is true
  92          */
  93         public static function checkPasswordCannotMatchUsername( $policyVal, User $user, $password ) {
  94                 $status = Status::newGood();
  95                 $username = $user->getName();
  96                 $contLang = MediaWikiServices::getInstance()->getContentLanguage();
  97                 if (
  98                         $policyVal && hash_equals( $contLang->lc( $username ), $contLang->lc( $password ) )
  99                 ) {
 100                         $status->error( 'password-name-match' );
 101                 }
 102                 return $status;
 103         }
 104
 105         /**
 106          * Check if username and password are on a blacklist of past MediaWiki default passwords.
 107          * @param bool $policyVal true to force compliance.
 108          * @param User $user
 109          * @param string $password
 110          * @return Status error if username and password match, and policy is true
 111          */
 112         public static function checkPasswordCannotMatchBlacklist( $policyVal, User $user, $password ) {
 113                 static $blockedLogins = [
 114                         'Useruser' => 'Passpass', 'Useruser1' => 'Passpass1', # r75589
 115                         'Apitestsysop' => 'testpass', 'Apitestuser' => 'testpass' # r75605
 116                 ];
 117
 118                 $status = Status::newGood();
 119                 $username = $user->getName();
 120                 if ( $policyVal ) {
 121                         if (
 122                                 isset( $blockedLogins[$username] ) &&
 123                                 hash_equals( $blockedLogins[$username], $password )
 124                         ) {
 125                                 $status->error( 'password-login-forbidden' );
 126                         }
 127
 128                         // Example from ApiChangeAuthenticationRequest
 129                         if ( hash_equals( 'ExamplePassword', $password ) ) {
 130                                 $status->error( 'password-login-forbidden' );
 131                         }
 132                 }
 133                 return $status;
 134         }
 135
 136         /**
 137          * Ensure that password isn't in top X most popular passwords, as defined by
 138          * $wgPopularPasswordFile.
 139          *
 140          * @param int $policyVal Cut off to use. Will automatically shrink to the max
 141          *   supported for error messages if set to more than max number of passwords on file,
 142          *   so you can use the PHP_INT_MAX constant here safely.
 143          * @param User $user
 144          * @param string $password
 145          * @since 1.27
 146          * @return Status
 147          * @see $wgPopularPasswordFile
 148          */
 149         public static function checkPopularPasswordBlacklist( $policyVal, User $user, $password ) {
 150                 global $wgPopularPasswordFile, $wgSitename;
 151                 $status = Status::newGood();
 152                 if ( $policyVal > 0 ) {
 153                         $langEn = Language::factory( 'en' );
 154                         $passwordKey = $langEn->lc( trim( $password ) );
 155
 156                         // People often use the name of the current site, which won't be
 157                         // in the common password file. Also check '' for people who use
 158                         // just whitespace.
 159                         $sitename = $langEn->lc( trim( $wgSitename ) );
 160                         $hardcodedCommonPasswords = [ '', 'wiki', 'mediawiki', $sitename ];
 161                         if ( in_array( $passwordKey, $hardcodedCommonPasswords ) ) {
 162                                 $status->error( 'passwordtoopopular' );
 163                                 return $status;
 164                         }
 165
 166                         // This could throw an exception, but there's not a good way
 167                         // of failing gracefully, if say the file is missing, so just
 168                         // let the exception fall through.
 169                         // Format of cdb file is mapping password => popularity rank.
 170                         // See maintenance/createCommonPasswordCdb.php
 171                         $db = CdbReader::open( $wgPopularPasswordFile );
 172
 173                         $res = $db->get( $passwordKey );
 174                         if ( $res && (int)$res <= $policyVal ) {
 175                                 // Note: If you want to find the true number of common
 176                                 // passwords stored (for reporting the error), you have to take
 177                                 // the max of the policyVal and $db->get( '_TOTALENTRIES' ).
 178                                 $status->error( 'passwordtoopopular' );
 179                         }
 180                 }
 181                 return $status;
 182         }
 183
 184         /**
 185          * Ensure the password isn't in the list of passwords blacklisted by the
 186          * wikimedia/password-blacklist library, which contains (as of 0.1.4) the
 187          * 100.000 top passwords from SecLists (as a Bloom filter, with an
 188          * 0.000001 false positive ratio).
 189          *
 190          * @param bool $policyVal Whether to apply this policy
 191          * @param User $user
 192          * @param string $password
 193          *
 194          * @since 1.33
 195          *
 196          * @return Status
 197          */
 198         public static function checkPasswordNotInLargeBlacklist( $policyVal, User $user, $password ) {
 199                 $status = Status::newGood();
 200                 if ( $policyVal && PasswordBlacklist\PasswordBlacklist::isBlacklisted( $password ) ) {
 201                         $status->error( 'passwordinlargeblacklist' );
 202                 }
 203
 204                 return $status;
 205         }
 206
 207 }